The Universe far beyond our own Milky Way Galaxy looks about the same in all directions. If you are given a picture of some arbitrary small piece of the sky that shows a measurement of your choice (for example, light, or the strength of radio waves, or numbers of galaxies per square degree), then you cannot tell in what direction that piece of sky can be found, except if you already knew that picture and recognized it.
That the Universe looks about the same in all directions is an important observation. Regions of space that are in opposite directions close to the edge of the visible Universe are so far apart that signals from one side have not had nearly enough time yet to reach the other side, so how can those two regions have adjusted their circumstances to one another? This is the so-called Horizon Problem.
The answer to this riddle is (according to modern views) that those two regions are now very far apart, but were so close together just before the Big Bang that pressure waves and heat could move to and fro between them until everything had just about the same temperature and density.
During the Big Bang there was a so-called Inflation Phase and during that phase the Universe increased in size by an incredible factor in a very short amount of time, so that the regions which used to be in close contact were suddenly so far apart that they have had no contact since that time, but yet still look very much alike.
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